A compact apparatus in which a specific point can be irradiated simultaneously by microwaves and ultrasound has been developed, The cavitation field produced by ultrasound is adjusted within a cavity to which the microwaves are introduced through the aperture of an Evenson-type cavity, The luminescence occurred during both the contraction and the expansion of bubble, The advantage of simultaneous irradiation by microwaves and ultrasound has been confirmed for both sono- and chemiluminescence.